Patent GB-1045949-A (GB)
Title: Magnetic separator
IPC: B03C1/253
Filed: 1965-04-09
Abstract: 1,045,949. Magnetic separators. D. WESTON. April 9, 1965, No. 15258/65. Heading B2J. A magnetic separator comprises a solenoid which is connected to a multiphase A.C. supply in such a way as to produce a series of N. and S. poles advancing along the solenoid for influencing the magnetic particles of a mixture of particles carried by a fluid vehicle along a tubular pathway disposed within the coils of the solenoid. As shown, the mixture is carried upwardly by gas (e.g. air or nitrogen) through a non-metallic tube 18. Magnetic particles come under the influence of the magnetic field, which is connected by tabs 14, 15, 16 to three phases of an A.C. supply, and are carried by the movement of the magnetic field in the direction of arrow C and out of the end of the tube 18 for collection in a hopper 34. The rate of movement of the magnetic field is arranged to be the same as that of the gas. Non-magnetic particles are drawn back through the space between an outer tubular casing 17 and the tube 18 by a fan 31 for discharge from a cyclone 32; any non-magnetic particles which are carried over with the magnetic particles are returned by the action of a countercurrent produced by a fan 32a. Baffles 30 prevent occlusion of non-magnetic particles in the concentration of magnetic particles in the tube 18. The tubes 17, 18 may be made of fibre glass or plastic. In Fig. 4 (not shown), the mixture is carried by a liquid, which may be water or brine, supplied from a tank 40 having a controlled inlet 41b and an agitator 43. The magnetic particles are carried through the surface 52 of the liquid to a collecting pan 49 and the non-magnetic particles are withdrawn by a pump 47. The rate of movement of the magnetic field is arranged to be greater than that of the liquid. The coils are immersed in a cooling system 50 through which a refrigerant is circulated. If required, cooling of the coils may be effected by circulating brine, or liquid helium or nitrogen through the coils which may be made of copper, high purity copper or niobium tin alloy tubing; cooling may also be effected by use of cooling coils embedded in the windings or by use of air-cooled heat conductors spaced between the coils. In Fig. 5 (not shown), the mixture is carried by a liquid through a horizontal tube. The magnetic particles are carried through the inclined surface 62 of the liquid to a collecting pan 65 and the non-magnetic particles drop through an opening in the bottom side of the tube for discharge through an outlet 66; the opening is provided with both a perforated plate 63 and a shutter controlled by a lever 67. To prevent magnetic particles from being discharged through the outlet 66, an upward movement is imparted to the mixture by a hydrofoil 64 positioned in front of the opening in the bottom side of the tube; magnetic particles are also prevented from passing through the perforated plate 63 by forming the plate as shown in either Fig. 2A or 2B (not shown). If desired the tube may be inclined instead of being horizontal. To provide an increase in the rate of movement of the magnetic field, the tap interval may be progressively increased along the length of the solenoid.